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arXiv · 2504.10627

Direct three-body atom recombination: halogen atoms

Rian Koots·Grace Ding·Jesús Pérez-Ríos
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Abstract

The recombination of halogen atoms has been a research topic in chemical physics for over a century. All theoretical descriptions of atom recombination depend on a two-step assumption, where two colliding atoms first form an unstable complex before a third colliding body either relaxes or reacts with it to yield a diatomic molecule. These mechanisms have served well in describing some of the dynamics of atom recombination, but have not yet provided a full theoretical understanding. In this work, we consider the role of the direct three-body recombination mechanism in halogen recombination reactions X + X + M $\rightarrow$ X$_2$ + M, where X is a halogen atom, and M is a rare gas atom. Our results agree well with experimental bromide and iodine recombination measurements, demonstrating that direct three-body recombination is essential in halogen recombination reactions.

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Rian Koots, Grace Ding, Jesús Pérez-Ríos. 2025-04-14. Direct three-body atom recombination: halogen atoms. https://arxiv.org/abs/2504.10627

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